Troubleshooting the 11 Most Common Film Related Problems with a VFFS

Information for almost any subject imaginable is available instantaneously. All you have to do is get out your phone, tablet or laptop, type in a word or question, and Voila! Instant feedback. In the packaging industry, people who have questions regarding troubleshooting issues with their VFFS machine can find the answer immediately…or can they? Sadly, with only a few exceptions, this is one area in which the Vertical Form Fill Seal machine has limited helpful online data, especially when it comes to troubleshooting mechanical issues in the field (which have a tendency to occur in the middle of third shift, am I right?)

Picture yourself managing operations, business flow or operating a VFFS and noticing that the film is not tracking properly. Wouldn’t it be easier, especially in this fast-paced world of online efficiency, to perform a quick online search of “Why is my film not tracking on VFFS?” Wouldn’t it then be frustrating to only get ads, websites or pamphlets that offer no immediate knowledge or solution?

No one likes unplanned downtime. It wastes resources, time, and money. Expeditiously finding the source of your workflow disruption prevents excessive downtime, disrupted production, and frustration! Although we love to hear from our customers and help out with any and all questions, that is not always the quickest, most convenient route for the operator or plant manager.

So, let’s begin to remedy the gap in available online information by looking at some mechanical issues regarding the most common area of concern with the VFFS – film. Allen Overmyer, using past and present knowledge of Rovema machines has provided decades of insight.

The 11 dilemmas we're looking to solve in this vffs troubleshooting article:

1. Film runs off-center
2. Film will not track
3. Film feed belts will not move
4. Bag Length is inconsistent
5. Bag Length is too long
6. Creases in film
7. Film Unwind is Difficult
8. Pulling film down the forming tube is difficult
9. Film jams at the forming tube
10. Film feed belts are slipping
11. Film is Sticking to the Vertical Seal

Dilemma #1: Film runs off-center

Troubleshoot:

• Roll of film is not centered on the film carriage or the spindle
• Film roll is improperly wound
• Film roll is loose on the spindle
• Belts are misaligned to the tube

Dilemma #2: Film will not track

Troubleshoot:

• The roll is not centered on spindle.
• Spindle is loose
• Film is not properly threaded on carriage

Dilemma #3: Film feed belts will not move

Troubleshoot:

• Check to see if belts are too tight against tube
• Check the film drive gear boxes and couplings
• Check the cables and drive for the film feed motor
• Check the bearings in the belt drive shaft

Dilemma #4: Bag Length is Inconsistent

Troubleshoot:

• Film is not threaded properly
• Film feed belt tension is improperly adjusted
• Film feed belts need to be cleaned

Dilemma #5: Bag Length is too long

Troubleshoot:

• Bag length is incorrectly set
• Reset bag length in control display
• Registration photo eye is not set correctly

Dilemma #6: Creases in film

Troubleshoot:

• Forming collar is worn out
• Forming collar is improperly adjusted
• Setup roller is improperly adjusted
• Valve is stuck on the forming collar, or rollers
• Contaminated roller in the film path
• Obstruction on the forming collar from printer

Dilemma #7: Film Unwind is Difficult

Troubleshoot:

• Forming part is dirty
• Film co-efficient of friction is too high
• Check guide rollers for foreign materials and free movement
• Zipper caught in collar
• Contact pressure of the belts too high
• Forming tube out of alignment

Dilemma #8: Pulling film down the forming tube is difficult

Troubleshoot:

• Forming set is dirty
• Film co-efficient of friction is too high
• Splice tape is caught in the collar
• Check the guide rollers for foreign materials and free movement
• Forming collar is not aligned properly to the tube
• Contact pressure of the belts is too high
• Setup rollers are out of alignment

Dilemma #9: Film jams at the forming tube

Troubleshoot:

• Vertical seal too hot, causing film to stick
• Too much pressure on the vertical seal band
• Film co-efficient of friction is too high
• If producing a stabilo bag, the seal is misaligned or too hot

Dilemma #10: Film feed belts are slipping

Troubleshoot:

• Not enough pressure on the film feed belts
• Belts are dirty
• Belts are worn
• Belts are misaligned to the tube
• Vacuum filter, or hoses, are clogged.
• Vacuum is turned off
• Film is not properly threaded

Dilemma #11: Film is Sticking to the Vertical Seal 

Troubleshoot:

• Heat is too high
• Too much pressure
• Vertical seal  or cross sealing jaws need cleaning
• Film is misaligned to expose the sealant material inside the bag to the heated seal band

Another consideration to contemplate is that a change in film structure, even if it is reported as having the same characteristics, can cause difficulty with running the machine after a roll change. Communication of a change to operators can help prevent confusion.

Many of the areas mentioned require a tweak, cleaning or small change of parts, however, if you don’t know what is causing the problem, how will you be able to efficiently resolve it? We would like to see that information readily available and easy to find for those who need it through the use of Tech Notes, articles and blogs. How would you like to see this information shared and what is important for you to know about troubleshooting your VFFS machine and the rest of your packaging line?

OEE (Overall Equipment Efficiency) and preventative maintenance are important - so then VFFS troubleshooting should be quick and infrequent. BUT if you're wrestling with these kinds of problems more often, maybe there's a bigger issue. Let us know! Shoot us an email, give us a phone call or just click here.